An efficient and practical methodology to obtain α-thio-β-dicarbonyl compounds was presented under alkaline conditions via potassium iodide (KI) catalysis.
在碱性条件下,通过碘化钾(KI)催化,提出了一种获得α-硫代-β-二羰基化合物的高效实用方法。
Identification of rapid access to polycyclic systems via a base-catalyzed cascade cyclization reaction and their biological evaluation
reaction between malonate esters and acrolein was developed to access complex polycyclic systems. This novel tandem reaction enables the simultaneous generation of up to seven new bonds and at least three new stereogenic centers. Mechanistic studies indicate a series of nucleophilic 1,4 and 1,6 Michael addition reactions occur, followed by an aldol condensation reaction, culminating in the formation of three
The highly enantioselective phase-transfer catalytic mono-alkylation of malonamic esters
作者:Mi-hyun Kim、Sea-hoon Choi、Yeon-Ju Lee、Jihye Lee、Keepyung Nahm、Byeong-Seon Jeong、Hyeung-geun Park、Sang-sup Jew
DOI:10.1039/b821468a
日期:——
The phase-transfer catalytic alkylation of N,N-dialkylmalonamic tert-butyl esters in the presence of 1 mol% of (S,S)-3,4,5-trifluorophenyl-NAS bromide afforded highly enantioselective (S)-mono-α-alkylated products (up to 96% ee), which could be readily converted into versatile chiral building blocks without loss of chirality.
Conformation of <i>N</i><sup>α</sup>-Substituted Hydrazino Acetamides in CDCl<sub>3</sub>, the Precious Help of the Analysis of Δδ between Amidic Hydrogens, and Correlation to the Conformation of Aza-β<sup>3</sup>-peptides
作者:Arnaud Salaün、Annaïck Favre、Barbara Le Grel、Michel Potel、Philippe Le Grel
DOI:10.1021/jo051887q
日期:2006.1.1
adopted by hydrazino acetamides 1a and 1b as model compounds for aza-β3-peptides. In this manner, it was possible to show that the amidic group of these compounds acts as a H-bond donor and interacts with two different H-bond acceptors. We concluded that the hydrazinoturn, a specific bifurcated H-bond system observed in the solid state, is also the preferred conformation of hydrazino acetamides 1a and 1b
α-Bromo-α,β-unsaturatedesters and α-bromobutenolides reacted with sodium salts of methyl malonamates to afford cyclopropanes, α-methoxycarbonyllactams and 5-amino-4-methoxycarbonyl-2,3-dihydrofurans. The last compounds could be easily converted into α-methoxycarbonyl-γ-lactones. The ratio of these compounds formed is influenced by the structures of both malonamates and unsaturated compounds, especially